A GENETICO-PHYSIOLOGICAL STUDY ON THE FORM.VTION ETC. 



47 



white graius scgregattxl l>y tlio latio 9 : !i : 4 iu the desceudauts of certsiiii 

 mitiu-al hybrids, and the red grain plants were purple-pigmentetl whereas the 

 gi'ey-brown plants were nnpigmented. A similar «ise was found in the cix)ss 

 tetween two Jajmuese varieties, " Otsubu " x " Hagiu-o ". Tlie grain of tl:e 

 former wiis psde biiH' ("white") and the latter was roddisli brown. Tn tlie 

 F. plaut.s the following result was obtained. 



T.VBLE 20. 



The yellowish l)rowu gi-ains were not fovmd iu the purple awn plants. 

 The ratios of coloured to white grains in each awn type showed a normal 

 3 : 1 ratio (see Table 20), so it is certain that a Hukage relation exists between 

 the genes for the pm-ple awn and for the reddish brown grain. With respect 

 to the colour of the awn, pui-ple and brown showed a 3 : 1 ratio, and iu the 

 palea, self pui-ple, locahzetl piu*ple, brown and yeUow segi'egated by the ratio 

 9:3:3:1 (155 : 45 : 44 : 16 obseiwed against 146.25 : 48.75 : 48.75 : 16.25 ex- 

 pected) aa in the case with the cross " Hanbuunento " X " Gem-okii-mochi ", 

 already reported in the section (c). These two crosses differ with respect to 

 the colour of paleas, only from the gene gi'oups which enter from the parental 

 plants, but the manner of segi-egation in the i^ generation is the same, thus : 



